Relaxation Parameter Mapping Adapted for 7T and Validation against Optimized Single Voxel MRS

Abstract

Previously published T1 relaxation times for brain tissue at 7T vary greatly in results and in methods. Only two publications have assessed in vivo T2 relaxation times in the human brain at 7T so far. We present the development and validation of T1 and T2 mapping sequences applicable at 7T in the presence of B1 inhomogeneity. For T1 mapping, a Look-Locker sequence with an adiabatic inversion prepulse and a modified fitting routine was implemented. For T2 mapping the vendor pre-implemented mixed imaging sequence was validated. For cross validation purpose T1 and T2 relaxation times were measured at selected anatomical locations by optimized SV-MRS parameter series